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JAEA Reports

Mizunami Underground Research Laboratory Project, Annual report for fiscal year 2019

Takeuchi, Ryuji; Onoe, Hironori; Murakami, Hiroaki; Watanabe, Yusuke; Mikake, Shinichiro; Ikeda, Koki; Iyatomi, Yosuke; Nishio, Kazuhisa*; Sasao, Eiji

JAEA-Review 2021-003, 63 Pages, 2021/06

JAEA-Review-2021-003.pdf:12.67MB

The Mizunami Underground Research Laboratory (MIU) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of geological disposal technologies through investigations of the deep geological environment in the crystalline rock (granite) at Mizunami City, Gifu Prefecture, central Japan. On the occasion of JAEA reformation in FY2014, JAEA identified three remaining important issues on the geoscientific research program based on the synthesized latest results of research and development (R&D): "Development of countermeasure technologies for reducing groundwater inflow", "Development of modeling technologies for mass transport" and "Development of drift backfilling technologies". At the MIU, the R&D are being pursued with a focus on the remaining important issues from FY2015, and satisfactory results have been achieved. Based on this situation, the R&D on the MIU Project were completed at the end of FY2019. In this report, the results of R&D and construction activities of the MIU Project in FY2019 are summarized.

JAEA Reports

Mizunami Underground Research Laboratory Project, Annual report for fiscal year 2013

Hama, Katsuhiro; Mikake, Shinichiro; Nishio, Kazuhisa; Kawamoto, Koji; Yamada, Nobuto; Ishibashi, Masayuki; Murakami, Hiroaki; Matsuoka, Toshiyuki; Sasao, Eiji; Sanada, Hiroyuki; et al.

JAEA-Review 2014-038, 137 Pages, 2014/12

JAEA-Review-2014-038.pdf:162.61MB

Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and the Phase III in fiscal year 2013. This report presents the results of the investigations, construction and collaboration studies in fiscal year 2013, as a part of the Phase II and Phase III based on the MIU Master Plan updated in 2010.

Journal Articles

Magnetic and electronic properties of (LaMnO$$_3$$)$$_5$$(SrMnO$$_3$$)$$_5$$ superlattice revealed by resonant soft X-ray scattering

Kubota, Masato; Yamada, Hiroyuki*; Nakao, Hironori*; Okamoto, Jun*; Yamasaki, Yuichi*; Sawa, Akihito*; Murakami, Yoichi*

Japanese Journal of Applied Physics, 53(5S1), p.05FH07_1 - 05FH07_5, 2014/05

https://doi.org/10.7567/JJAP.53.05FH07
 Times Cited Count：2 Percentile：8.84(Physics, Applied)

Journal Articles

Antiferromagnetic order of the Co$$^{2+}$$ high-spin state with a large orbital angular momentum in La$$_{1.5}$$Ca$$_{0.5}$$CoO$$_{4}$$

Okamoto, Jun*; Nakao, Hironori*; Yamasaki, Yuichi*; Wadachi, Hiroki*; Tanaka, Arata*; Kubota, Masato; Horigane, Kazumasa*; Murakami, Yoichi*; Yamada, Kazuyoshi*

Journal of the Physical Society of Japan, 83(4), p.044705_1 - 044705_6, 2014/04

https://doi.org/10.7566/JPSJ.83.044705
 Times Cited Count：9 Percentile：55.36(Physics, Multidisciplinary)

Journal Articles

Spin state of Co$$^{3+} $$ in LaCo$$_{1-x}$$ Rh$$_{x}$$O$$_{3}$$ investigated by structural phenomena

Asai, Shinichiro*; Okazaki, Ryuji*; Terasaki, Ichiro*; Yasui, Yukio*; Kobayashi, Wataru*; Nakao, Akiko*; Kobayashi, Kensuke*; Kumai, Reiji*; Nakao, Hironori*; Murakami, Yoichi*; et al.

Journal of the Physical Society of Japan, 82(11), p.114606_1 - 114606_6, 2013/11

https://doi.org/10.7566/JPSJ.82.114606
 Times Cited Count：6 Percentile：43.5(Physics, Multidisciplinary)

Neutron and synchrotron X-ray diffraction for LaCo$$_{1-x}$$ Rh$$_{x}$$O$$_{3}$$ have been carried out in order to investigate the structural properties related with the spin state of Co$$^{3+}$$ ions. We have found that the values of the Co(Rh)-O bond lengths in the Co(Rh)O$$_{6}$$ octahedron of LaCo$$_{0.8}$$Rh$$_{0.2}$$O$$_{3}$$ are nearly identical at 10 K. The lattice volume for the Rh$$^{3+}$$ substituted samples decreases with the thermal expansion coefficient similar to that of LaCoO$$_{3}$$ from room temperature, and ceases to decrease around 70 K. These experimental results favor a mixed state consisting of the high-spin state and low-spin state Co$$^{3+}$$ ions, and suggest that the high-spin state Co$$^{3+}$$ ions are thermally excited in addition to those pinned by the substituted Rh$$^{3+}$$ ions.

Journal Articles

Sagittal focusing of synchrotron radiation X-rays using a winged crystal

Nisawa, Atsushi*; Yoneda, Yasuhiro; Ueno, Go*; Murakami, Hironori*; Okajima, Yuka*; Yamamoto, Kenichiro*; Semba, Yasunori*; Uesugi, Kentaro*; Tanaka, Yoshihito*; Yamamoto, Masaki*; et al.

Journal of Synchrotron Radiation, 20(2), p.219 - 225, 2013/03

https://doi.org/10.1107/S0909049512049813
 Times Cited Count：12 Percentile：54.28(Instruments & Instrumentation)

A Si(111) winged crystal has been designed to minimize anticlastic bending and improve sagittal focusing efficiency. The crystal was thin with wide stiffening wings. The length-to-width ratio of the crystal was optimized by finite element analysis, and the optimal value was larger than the "golden value". The analysis showed that the slope error owing to anticlastic bending is less than the Darwin width. The X-rays were focused two-dimensionally using the crystal and a tangentially bent mirror. The observed profiles of the focal spot agreed well with the results of a ray-tracing calculation in the energy range from 8 to 17.5 keV. X-ray diffraction measurements with a high signal-to-noise ratio using this focusing system were demonstrated for a small protein crystal.

Journal Articles

Emergent phenomena in perovskite-type manganites

Taguchi, Yasujiro*; Sakai, Hideaki*; Okuyama, Daisuke*; Ishiwata, Shintaro*; Fujioka, Jun*; Fukuda, Tatsuo; Hashizume, Daisuke*; Kagawa, Fumitaka*; Takahashi, Yoichiro*; Shimano, Ryo*; et al.

Physica B; Condensed Matter, 407(11), p.1685 - 1688, 2012/06

https://doi.org/10.1016/j.physb.2012.01.006
 Times Cited Count：5 Percentile：23.98(Physics, Condensed Matter)

Journal Articles

Magnetic phase diagrams of YVO$$_{3}$$ and TbVO$$_{3}$$ under high pressure

Bizen, Daisuke*; Nakao, Hironori*; Iwasa, Kazuaki*; Murakami, Yoichi*; Osakabe, Toyotaka; Fujioka, Jun*; Yasue, Toshio*; Miyasaka, Shigeki*; Tokura, Yoshinori*

Journal of the Physical Society of Japan, 81(2), p.024715_1 - 024715_6, 2012/02

https://doi.org/10.1143/JPSJ.81.024715
 Times Cited Count：6 Percentile：42.8(Physics, Multidisciplinary)

The magnetic phase diagrams for $$R$$VO$$_{3}$$ ($$R$$ = Y, Tb) were determined by low temperature and high pressure neutron-diffraction techniques. We found that the magnetic ground state in TbVO$$_{3}$$ changes from ${it C}$-type spin ordering (${it C}$-SO) to ${it G}$-type spin ordering (${it G}$-SO) on application of pressure. The transition of the magnetic ground state also indicates that the ground state of the orbital ordering changes from ${it G}$-type orbital ordering (${it G}$-OO) to ${it C}$-type orbital ordering (${it C}$-OO). In YVO$$_{3}$$, the ${it G}$-SO and ${it C}$-OO phases set in simultaneously up to 6.2 GPa, and the disorder-[${it G}$-SO, ${it C}$-OO] phase transition appears above 6 GPa. This is the first observation of a simultaneous spin and orbital order-disorder phase transition in perovskite-type transition-metal oxides $$R$$MO$$_{3}$$. The [${it G}$-SO, ${it C}$-OO] phase is strongly stabilized with increasing pressure, and both the covalency effect and the superexchange interaction play roles in this stabilization.

Journal Articles

X-ray photon correlation spectroscopy study in valence fluctuation compound Eu$$_{3}$$S$$_{4}$$

Nakao, Hironori*; Owada, Kenji; Shimomura, Susumu*; Ochiai, Akira*; Namikawa, Kazumichi*; Mizuki, Junichiro; Mimura, Hidekazu*; Yamauchi, Kazuto*; Murakami, Yoichi*

AIP Conference Proceedings 1234, p.935 - 938, 2010/06

https://doi.org/10.1063/1.3463370
 Times Cited Count：2 Percentile：66.93(Physics, Applied)

Journal Articles

Application of laser-accelerated protons to the demonstration of DNA double-strand breaks in human cancer cells

Yogo, Akifumi; Sato, Katsutoshi; Nishikino, Masaharu; Mori, Michiaki; Teshima, Teruki*; Numasaki, Hodaka*; Murakami, Masao*; Demizu, Yusuke*; Akagi, Takashi*; Nagayama, Shinichi*; et al.

Applied Physics Letters, 94(18), p.181502_1 - 181502_3, 2009/05

https://doi.org/10.1063/1.3126452
 Times Cited Count：110 Percentile：94.75(Physics, Applied)

Journal Articles

Structural phase transition in the spin gap system YbAl$$_3$$C$$_3$$

Matsumura, Takeshi*; Inami, Toshiya; Kosaka, Masashi*; Kato, Yoshiaki*; Inukai, Takaki*; Ochiai, Akira*; Nakao, Hironori*; Murakami, Yoichi*; Katano, Susumu*; Suzuki, Hiroyuki*

Journal of the Physical Society of Japan, 77(10), p.103601_1 - 103601_4, 2008/10

https://doi.org/10.1143/JPSJ.77.103601
 Times Cited Count：14 Percentile：62.95(Physics, Multidisciplinary)

Journal Articles

Devil's flower resulting from a successive charge disproportionation of NaV$$_{2}$$O$$_{5}$$; Understanding of the details of the Ising spin and the competitive interactions which made the devil's flower bloom

Owada, Kenji; Fujii, Yasuhiko; Muraoka, Jiro*; Nakao, Hironori*; Murakami, Yoichi*; Noda, Yukio*; Osumi, Hiroyuki*; Ikeda, Naoshi*; Shobu, Takahisa; Isobe, Masahiko*; et al.

Hoshako, 21(2), p.87 - 96, 2008/03

http://ci.nii.ac.jp/naid/10020476047

Devil's flower has been found in a temperature-pressure phase diagram of NaV$$_{2}$$O$$_{5}$$, which shows a charge disproportionation (CD) at ambient pressure. By a complementary use of an X-ray structural analysis and a resonant X-ray diffraction, which is sensitive to CD, we have investigated the structural relationship between two ground states appeared in lower and higher pressure regions including the charge arrangements. It has been clarified that two equivalent types of charge arrangement in CD correspond to the Ising variable in NaV$$_{2}$$O$$_{5}$$. The atomic shifts are regarded as linearly coupled to the Ising spins. The results lead us to the conclusion that it is the first time that the devil's flower blooms in a charge-disproportionation system. The results also lead us to a hypothesis that the competitive interactions between a Ising spins may result from the Ising spin-phonon coupling.

Journal Articles

Structural relations between two ground states of NaV$$_{2}$$O$$_{5}$$ under high pressure; A Synchrotron X-ray diffraction study

Owada, Kenji; Fujii, Yasuhiko; Muraoka, Jiro*; Nakao, Hironori*; Murakami, Yoichi; Noda, Yukio*; Osumi, Hiroyuki*; Ikeda, Naoshi*; Shobu, Takahisa; Isobe, Masahiko*; et al.

Physical Review B, 76(9), p.094113_1 - 094113_10, 2007/09

https://doi.org/10.1103/PhysRevB.76.094113
 Times Cited Count：10 Percentile：44.52(Materials Science, Multidisciplinary)

Structural relations between two ground states of the ANNNI (Axial Next Nearest Neighbor Ising) compound NaV$$_{2}$$O$$_{5}$$, C$$_{1/4}$$- and C$$_{0}$$-phases below and above the transition pressure $$P_{rm C}$$ = 1 GPa, were investigated by X-ray diffraction and scattering techniques. The structure of the C$$_{0}$$-phase is well explained by the $$A$$($$A'$$) pattern which is one of four layers ($$AAA'A'$$) of the C$$_{1/4}$$-phase, however, the amount of the atomic shifts under the conditions 1.6 GPa and 6 K is 27% that under ambient pressure. On the other hand, resonant X-ray scattering showed that the charges are disproportionated under high pressure. Based on these facts, it was concluded that charge disproportionation corresponds to the Ising variable in NaV$$_{2}$$O$$_{5}$$, where the atomic shifts are regarded as linearly coupled to the Ising spins. These results lead to the hypothesis that the competitive interactions between the Ising spins may result from the Ising spin-phonon coupling.

Journal Articles

Resonant X-ray magnetic diffraction experiments on SmB$$_2$$C$$_2$$

Inami, Toshiya; Homma, Tetsuo*; Tsutsui, Satoshi*; Indo, Kentaro*; Onodera, Hideya*; Ishii, Kenji; Owada, Kenji; Kuzushita, Kaori*; Nakao, Hironori*; Murakami, Yoichi*

Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.748 - 750, 2007/03

We investigated successive phase transitions in SmB$$_2$$C$$_2$$ at $$T_{rm N2}$$=37K and $$T_{rm N1}$$=51K by means of resonant X-ray diffraction. Strong resonant diffraction signal is observed at the 101 reflection below $$T_{rm N2}$$ at the Sm $$L_3$$ edge, whereas in the intermediate phase signals appear at incommensurate positions $${vec Q}$$=(1$$pmdelta$$, $$pmdelta$$,1) where $$delta$$=0.13. Accordingly, the successive phase transitions in SmB$$_2$$C$$_2$$ is found to be commensurate-to-incommensurate magnetic phase transitions.

Journal Articles

Coherent X-ray diffraction for domain observation

Owada, Kenji; Namikawa, Kazumichi; Mizuki, Junichiro; Shimomura, Susumu*; Nakao, Hironori*; Ito, Kazuki*; Matsushita, Mitsuyoshi*; Yoneda, Yasuhiro; Murakami, Yoichi*; Hirota, Kazuma*

Transactions of the Materials Research Society of Japan, 32(1), p.7 - 10, 2007/03

An X-ray speckle pattern well reflects a particle or domain alignment on the inside of materials. Detecting the alignment is important for understanding a function of the materials such as ferroelectric, piezoelectric materials, photonic crystals and so on. We have thus constructed the apparatus for coherent X-ray diffraction at BL22XU@SPring-8, high quality slits for obtaining the full coherent X-ray beam, high resolution X-ray CCD camera for obtaining the well-resolved speckle pattern, and so on. By using the devices, we have successfully observed the speckle pattern from Cu$$_{3}$$Au, the ferroelectric material PZN-9%PT (91%Pb(Zn$$_{1/3}$$Nb$$_{2/3}$$)O$$_{3}$$-9%PbTiO$$_{3}$$) and Sr-doped BaTiO$$_{3}$$. The 2DFFT image gives us a spatial autocorrelation function which includes the information of the arrangement of the domains in the crystal within micrometers scale.

Journal Articles

Discovery of the "Devil's flower" in a charge-ordering system; Synchrotron X-ray diffraction study of NaV$$_{2}$$O$$_{5}$$

Owada, Kenji; Fujii, Yasuhiko; Nakao, Hironori*; Murakami, Yoichi*; Isobe, Masahiko*; Ueda, Yutaka*

Modern Physics Letters B, 20(5), p.199 - 214, 2006/02

https://doi.org/10.1142/S0217984906010548
 Times Cited Count：5 Percentile：21.81(Physics, Applied)

We review recent synchrotron diffraction studies of NaV$$_{2}$$O$$_{5}$$. The resonant X-ray scattering performed on a monoclinically-split single domain of NaV$$_{2}$$O$$_{5}$$ shows a critically enhanced contrast between V$$^{4+}$$ and V$$^{5+}$$ ions. The results has led us to the unequivocal conclusion of the charge-order pattern of low-temperature phase of NaV$$_{2}$$O$$_{5}$$ below $$T_{rm c}$$ = 35 K. In spite of the possible four types of configuration of the zig-zag-type charge-order patterns in the $$ab$$-plane (A, A', B and B'), the stacking sequence along the $$c$$-axis is determined as the AAA'A' type by comparison with model calculations. By assigning the A and A' configurations to Ising spins $$uparrow$$ and $$downarrow$$, one can reasonably explain the previously discovered "devil's staircase"-type behavior with respect to the modulation of layer-stacking sequences at high pressures and low temperatures, which clearly resembles the global phase diagram theoretically predicted by the ANNNI model, called "devil's flower". This is the first case that the devil's flower appears in such a charge-ordering system, where charge-order patterns are regarded as Ising spins.

Journal Articles

Charge-order pattern of the low-temperature phase from a monoclinic single domain of NaV$$_{2}$$O$$_{5}$$ uniquely determined by resonant X-ray scattering

Owada, Kenji; Fujii, Yasuhiko; Katsuki, Yuya*; Muraoka, Jiro*; Nakao, Hironori*; Murakami, Yoichi; Sawa, Hiroshi*; Ninomiya, Emi*; Isobe, Masahiko*; Ueda, Yutaka*

Physical Review Letters, 94(10), p.106401_1 - 106401_4, 2005/03

https://doi.org/10.1103/PhysRevLett.94.106401
 Times Cited Count：24 Percentile：72.16(Physics, Multidisciplinary)

The present resonant X-ray scattering has been performed on a monoclinically-split single domain of NaV$$_{2}$$O$$_{5}$$. The observation of a critically enhanced contrast between V$$^{4+}$$ and V$$^{5+}$$ ions has led us to the unequivocal conclusion of the charge-order pattern of low-temperature phase of NaV$$_{2}$$O$$_{5}$$ below $$T_{rm c}$$ = 35 K. In spite of the possible four types of configuration of the zig-zag-type charge-order patterns in the $$ab$$-plane (A, A', B and B'), the stacking sequence along the $$c$$-axis is determined as the AAA'A' type by comparison with model calculations. By assigning the A and A' configurations to Ising spins, one can reasonably explain the previously discovered "devil's staircase"-type behavior with respect to the modulation of layer-stacking sequences at high pressures and low temperatures, which clearly resembles the global phase diagram theoretically predicted by the ANNNI model.

Journal Articles

Resonant X-ray scattering study on the filled skutterudite PrFe$$_4$$P$$_{12}$$

Ishii, Kenji; Inami, Toshiya; Murakami, Yoichi; Hao, L.*; Iwasa, Kazuaki*; Kogi, Masafumi*; Aoki, Yuji*; Sugawara, Hitoshi*; Sato, Hideyuki*; Imada, Shin*; et al.

Physica B; Condensed Matter, 329-333(1-4), p.467 - 468, 2003/05

https://doi.org/10.1016/S0921-4526(02)02037-9
 Times Cited Count：6 Percentile：35.62(Physics, Condensed Matter)

Resonant x-ray scattering study was carried out to investigate an anomalous ordered state ($$T_A$$ = 6.5 K) in the filled skutterudite PrFe$$_4$$P$$_{12}$$. At the Pr-$$L_{III}$$ absorption edge, we observed resonant features in $$h+k+l$$ = odd reflections, which are forbidden in the $$bcc$$ structure above $$T_A$$. Because these reflections contain the difference of anomalous scattering factor between two Pr atoms in the $$bcc$$ unit cell, and the ordered state is attributed to the ordering of two different electronic states of Pr.

Journal Articles

Orbital excitations in LaMnO$$_3$$ studied by resonant inelastic X-ray scattering

Inami, Toshiya; Fukuda, Tatsuo; Mizuki, Junichiro; Ishihara, Sumio*; Kondo, Hiroshi*; Nakao, Hironori*; Matsumura, Takeshi*; Hirota, Kazuma*; Murakami, Yoichi*; Maekawa, Sadamichi*; et al.

Physical Review B, 67(4), p.045108_1 - 045108_6, 2003/01

https://doi.org/10.1103/PhysRevB.67.045108
 Times Cited Count：56 Percentile：87.96(Materials Science, Multidisciplinary)

We report resonant inelastic x-ray scattering experiments of the orbitally ordered manganite LaMnO$$_3$$. When incident photon energy is tuned near the Mn $$K$$ absorption edge, the spectra reveal three features at 2.5 eV, 8 eV and 11 eV. The 8 eV and 11 eV peaks are ascribed to transitions from the O 2$$p$$ bands to the empty Mn 3$$d$$ and $$4s$$/$$4p$$ bands, respectively. On the other hand, the 2.5 eV peak is considered an orbital excitation across the Mott gap, ${it i.e.}$ an electron excitation from the effective lower Hubbard band with the $$d_{3x^2-r^2}$$ and $$d_{3y^2-r^2}$$ orbital characters to the upper Hubbard band with the $$d_{y^2-z^2}$$ and $$d_{z^2-x^2}$$ ones. The weak dispersion and characteristic azimuthal angle dependence of this excitation are well reproduced by a theory which includes orbital degeneracy and strong electron correlation.

Journal Articles

An Inelastic X-ray scattering spectrometer for materials science on BL11XU at SPring-8

Inami, Toshiya; Fukuda, Tatsuo; Mizuki, Junichiro; Nakao, Hironori*; Matsumura, Takeshi*; Murakami, Yoichi*; Hirota, Kazuma*; Endo, Yasuo*

Nuclear Instruments and Methods in Physics Research A, 467-468(Part.2), p.1081 - 1083, 2001/07

https://doi.org/10.1016/S0168-9002(01)00731-8
 Times Cited Count：20 Percentile：79.16(Instruments & Instrumentation)

no abstracts in English

34 (Records 1-20 displayed on this page)